Regarding native bees vs honey bees, there are distinct camps which make the case for these categories of pollinators. Pollination is never either/or. Pollination is done by a web of pollinators, just as many of them rely on a myriad of food sources. It is far less common for a plant to be tightly linked to a single pollinator, although this occurs. Further, there are many regional differences as well as seasonality. My thinking has always been that growers rent bees as insurance. They know that native bees can do a heck of a good job pollinating -- if they are abundant. Some years they are, some places they are. Others, not so much. 

> In British Columbia, pollination service increased with abundance of wild bumble bees, whereas in Michigan the abundance of honey bees was the primary predictor of pollination. The proportion of semi-natural habitat at local and landscape scales was positively correlated with wild bee abundance in both regions. Wild bee abundance declined significantly with distance from natural borders in Michigan, but not in British Columbia where large-bodied bumble bees dominated the wild bee community. Our results highlight the varying dependence of crop production on different types of bees and reveal that strategies for pollination improvement in the same crop can vary greatly across production regions.

Gibbs, Jason, et al. "Contrasting Pollinators and Pollination in Native and Non-Native Regions of Highbush Blueberry Production." PloS one 11.7 (2016): e0158937.

> The survey assesses grower perceptions of native pollinators' effectiveness and their perceptions of native pollinators' contribution to fruit set. Results indicate a widespread perception among growers of native pollinators' importance. While native pollinators are not effective enough to replace rented honey bees for three-quarters of the industry, they are broadly seen as an important form of insurance in poor weather when honey bees' effectiveness is reduced. The main obstacle to greater utilization of native pollinators found in this study was uncertainty over native pollinators' contribution to yield and the associated difficulty monitoring native pollinators' population size.

Hanes, Samuel P., et al. "Grower perceptions of native pollinators and pollination strategies in the lowbush blueberry industry." Renewable Agriculture and Food Systems 30.02 (2015): 124-131.

>  Though most blueberry growers in eastern Canada use managed bees in lowbush blueberry pollination, native pollinators are recognized as an important component of the pollination service provision. In this study we examined the diversity and abundance of native bees in lowbush blueberry fields in Nova Scotia, while considering spatial and temporal patterns in their distribution over the growing season. In total, we collected 95 species representing 13 genera, of which Lasioglossum and Andrena comprised >92% of all individuals. ... The results highlight wild bee taxa that could be targeted for conservation efforts to potentially decrease reliance on managed pollinators.

Cutler, G. Christopher, et al. "Wild bee pollinator communities of lowbush blueberry fields: Spatial and temporal trends." Basic and Applied Ecology 16.1 (2015): 73-85.

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